I. Priority
This application claims priority from design patent application No. 29/142,904 filed Jun. 5, 2001, and entitled xe2x80x9cSandal Portionsxe2x80x9d.
II. Field of the Invention
The present invention relates to footwear constructions, and more particularly to a sandal construction.
III. Description of the Art
Sandals have typically functioned as casual footwear, providing only limited support and stability. As a result, traditional sandals were not well suited for use in athletic and sporting applications. More recently, however, sandals have evolved to provide increased support and stability, making them more suitable for a variety of athletic and sporting applications. These improvements have resulted primarily from advances in the sole and in the strapping system. Although there has been marked growth in the comfort and support provided by sandals, footwear manufacturers continue to search for technologies capable of further enhancing the comfort and support of sandals.
Conventional sport sandals include a contoured sole and a strapping system for retaining the sole against the bottom of a foot. Typical sandals of this type include a front strap for retaining the forefoot, and ankle and heel straps for retaining the rear portion of the foot. The front strap extends over the forefoot of the foot and includes opposite ends which are generally affixed to the sole. The front strap is typically length-adjustable to permit the sandal to be adjusted to snuggly fit different size feet. The ankle strap extends over the top surface of the foot just in front of the ankle and includes opposite ends affixed to inner and out ankle posts or directly to the sole. The heel strap wraps around the rear heel portion of the foot and, like the ankle strap, is affixed to the ankle posts or directly to the sole. As with the front strap, at least one of the ankle or heel strap is typically adjustable in length to permit the sandal to be adjusted to snuggly fit different size feet. These conventional two-strap systems require two separate adjustments to properly secure the sandal on the wearer""s foot. As a result, the front strap is often adjusted to provide a loose fit so that the forefoot can be easily slipped into and out of the sandalxe2x80x94leaving only the ankle or heel strap to be adjusted each time the sandal is worn. Although this makes it easier to put on the sandal, it can, unfortunately, reduce the foot support provided by the sandal and potentially lead to foot or ankle injury.
Some manufacturers have simplified the strap system by using a single adjustable strap that extends from the ankle region over the forefoot and then back to the ankle region. By adjusting this single strap, sandal is secured on the foot and the fit of the sandal in both the ankle and forefoot regions is controlled. A conventional sandal having a single adjustable strap is shown in FIG. 1. As illustrated, the sandal 150 includes a sole 152 and a strap 160. The strap 160 is attached to a medial post 170 at one end, is threaded through the sole 152 and over the foot, and is threaded through a buckle 172 that is attached to a lateral post 174. The strap 160 is positioned on the sole 152 to cross over itself in the front portion of the sandal, with the two crossed strap portions defining a forefoot strap. The strap 160 passes freely through the sole 152 so that pulling one end of the strap 160 results in tightening the entire strap, including in both the forefoot and ankle regions.
Although this strapping system keeps the sandal 150 attached to the foot, the strap 160 is configured to crosses over itself in the forefoot region near the lateral edge of the sandal. The laterally disposed crossover 171 may permit the foot to move within the sandal, possibly reducing support over the forefoot as a whole and causing discomfort. In addition to crossing over itself in the forefoot region, the strap 160 also crosses over itself just in front of the ankle at crossover 173 These two crossovers 171 and 173 create pressure points that may cause chafing and discomfort both while the strap 160 is being adjusted and during walking. This problem is only exacerbated as the strap is increasingly tightened. Further, because the strap 160 moves with respect to the sole 152, there is a potential for the strap 160 to rub against and cause significant wear of the sole 152. To address this concern, the sole 152 must manufactured from harder, more wear-resistant materials, such as polyurethane. Unfortunately, anti-bacterial components, such as Microban(copyright) available from Microban Products Company, cannot be added to polyurethane and other similar components. As a result, sandals manufactured from this material are subject to odor control issues. This is a particularly acute problem with sandals because they are often worn in wet and dirty environments, where bacteria can readily contaminate the sole. To address this concern, manufacturers typically recommend periodic washing of the sandal. This is inconvenient and burdensome, so much so that it is often not done.
Additionally, conventional sandals of this type are difficult to adjust when under load. Although the sole 152 is manufactured from a relatively hard material, it is, by design, sufficiently soft to provide some level of cushioning (e.g. some level of compression when under load). As a result, the sole 152 will compress under load, pinching those portions of the strap that pass through the sole 152. Significant loads can make it difficult, if not impossible, for the wearer to manually adjust the strap.
The aforementioned problem are overcome by the present invention wherein a sandal construction is provided with an adjustable strap that passes through the sole and over the foot forming a crossover at substantially the center of the forefoot.
In a preferred embodiment, the sandal includes a strapping system having medial and lateral posts positioned on opposite sides of the ankle. A heel strap extends between the posts around the heel. The strapping system also includes a front strap that extends between the ankle and forefoot regions of the sandal. The strap includes a first end that is secured to the sole in the forefoot region. The strap crisscrosses over substantially the center of the foot in the forefoot region and then extends rearwardly to an ankle post.
In a more preferred embodiment, the sole defines a plurality of channels passing between the lateral and medial sides of the sandal to permit passage of the front strap. The sole further defines spaced apertures near each edge of the sole to allow the front strap to pass into the channels from the upper side of the sandal.
In an even more preferred embodiment, the sole includes a flexplate disposed between a midsole and an outsole. The flexplate is substantially rigid providing support and stability to the sandal. The flexplate may also define the channels through which the front strap passes. Covers may be placed over the channels to entrap the strap in rigid tunnels.
The present invention provides a sandal having a continuous front strap that permits simultaneous adjustment in both the ankle and heel regions as the sandal is secured to the foot. The front strap is relatively easy to adjust and is positioned on the sole to provide improved comfort and support. The substantially centered crossover in the forefoot region provides improved comfort and lateral stability. Further, the flexplate reduces wear in the midsole by providing a hard surface for the strap to move against. This permits the midsole to be manufactured from softer materials, including various materials that can be impregnated with an anti-bacterial component to reduce bacterial growth. The flexplate also provides a low friction surface to ease movement of the strap during adjustment. Also, the flexplate channels facilitate manufacture by positively and easily locating the straps. The flexplate covers enclose the straps in rigid tunnels. This protects the straps from being pinched by the sole, and permits easy adjustment even under when the sandal is under load.
These and other objects, advantages, and features of the invention will be more readily understood and appreciated by reference to the detailed description of the preferred embodiment and the drawings.